1. Field
The present disclosure relates to imaging devices such as digital still cameras and the like, and more particularly to imaging devices that allow image interference caused by an external noise to be reduced.
2. Description of the Related Art
In recent years, opportunities are increased in which imaging devices such as digital still cameras and the like are used in environments where portable information terminals, such as mobile telephones and PHSs (personal handyphone systems), which emit electromagnetic waves, are used. Further, there may be opportunities of imaging devices such as digital still cameras and the like being used in environments where intense electromagnetic waves are emitted, e.g. in the vicinity of a radio station or a television station.
In a case where the imaging device is used in such an environment, the imaging device is likely to be subjected to an electromagnetic interference. Hereinafter, an environment in which imaging devices are likely to be subjected to such an electromagnetic interference is referred to as an “intense electric field environment.” If an imaging device such as a digital still camera is used in the intense electric field environment, an image taken by the imaging device may contain a stripe pattern noise (beat noise), and image interference may be caused.
The higher a performance of an imaging element of the imaging device is (the higher the sensitivity of an imaging element to be used is), the more significant the image interference is. Further, in an imaging element built into an imaging device having been downsized as a result of the sizes of imaging devices being reduced, an amount of coupling of intense electric field noise from the outside is increased, so that the image interference becomes more significant.
Causes of the image interference include entering of an external electromagnetic wave into an image signal line of an imaging element. Therefore, as the conventional arts, a structure is disclosed in which an electrically-conductive filter is additionally provided on a surface of a lens, and an imaging element is shielded from intense electric field noises which may enter the imaging element (see, for example, Japanese Laid-Open Patent Publication No. 2008-211378).